Reference Guide

218 | Border Gateway Protocol
www.dell.com | support.dell.com
Use the clear ip bgp command in EXEC Privilege mode at the system prompt to reset a BGP connection
using BGP soft reconfiguration.
When soft-reconfiguration is enabled for a neighbor and the
clear ip bgp soft in command is executed, the
update database stored in the router is replayed and updates are reevaluated. With this command, the replay
and update process is triggered only if route-refresh request is not negotiated with the peer. If the request is
indeed negotiated (upon execution of
clear ip bgp soft in), then BGP sends a route-refresh request to the
neighbor and receives all of the peer’s updates.
To use soft reconfiguration, or soft reset, without preconfiguration, both BGP peers must support the soft
route refresh capability, which is advertised in the open message sent when the peers establish a TCP
session.
To determine whether a BGP router supports this capability, use the
show ip bgp neighbors command. If
a router supports the route refresh capability, the following message should be displayed:
Received route refresh capability from peer.
If you specify a BGP peer group by using the peer-group-name argument, all members of the peer group
inherit the characteristic configured with this command.
The following (Figure 8-33) enables inbound soft reconfiguration for the neighbor 10.108.1.1. All updates
received from this neighbor are stored unmodified, regardless of the inbound policy. When inbound soft
reconfiguration is done later, the stored information is used to generate a new set of inbound updates.
Figure 8-33. Command example: router bgp
Command Syntax Command Mode Purpose
clear ip bgp {* |
neighbor-address | AS Numbers
| ipv4 | peer-group-name} [soft
[in | out]]
EXEC Privilege Clear all information or only specific details.
*: Clear all peers
neighbor-address: Clear the neighbor with this IP
address
AS Numbers: Peers’ AS numbers to be cleared
ipv4: Clear information for IPv4 Address family
peer-group-name: Clear all members of the specified
peer group
neighbor {ip-address |
peer-group-name}
soft-reconfiguration inbound
CONFIG-ROUTER-BGP Enable soft-reconfiguration for the BGP neighbor
specified. BGP stores all the updates received by the
neighbor but does not reset the peer-session.
Entering this command starts the storage of updates, which is required to do inbound
soft reconfiguration. Outbound BGP soft reconfiguration does not require inbound soft
reconfiguration to be enabled.
FTOS>router bgp 100
neighbor 10.108.1.1 remote-as 200
neighbor 10.108.1.1 soft-reconfiguration inbound